A TV viewer who wants to record and watch a program imagines the program from program information on newspaper, TV guide, or the like, becomes interested in the program, and records it. However, the actually recorded program may be a disappointment against the user's expectations. It is convenient if the user can determine the contents of a recorded program somewhat by watching its digest version.
Additionally, it is hard to properly decide to rent or buy movie software or a documentary video at a store only by its name or brief synopsis that introduces the contents. However, if the digest video is available, the contents can be more appropriately determined.
Conventionally, a digest video is generated by capturing still images at a predetermined time interval and sequentially displaying them at a high speed, capturing moving images at a predetermined period and sequentially continuously displaying them, detecting the motion on the screen (by motion detection using luminance and color different signals or a method using histogram of pixels) to acquire scene change information, selecting representative images on the basis of the information, and sequentially displaying the images, extracting and recording a feature point from an audio signal, or combining the above techniques.
However, a video of certain kind cannot be understood unless many points are generally presented. The digest of another video preferably excludes the ending. For still another video, only scenes with motions are preferably put into the digest. That is, the composition of the optimum digest video changes depending on the field, i.e., type of video to be recorded.
In addition, the requirement for a digest video also changes depending on the type of video. More specifically, the user sometimes requires a digest video to present the summary in detail as much as possible. However, in other cases, he/she wants to see the representative scenes or the time-sequential development of the scenes or requires the digest video to function as a promotion video. The prior art cannot completely meet these requirements.
In a digest video containing only video data, the audio data is not played back, and the content preview may be insufficient. In the prior art, if the audio data is also played back in the digest video, playback may start or stop in the middle of words, and they are very hard to listen to.